Metallic structural element



July as, 1925. 1,547,607

N. C. RENDLEMAN METALLIC STRUCTURAL ELEMENT Filed Feb. 13, 1922 2Sheets-Sheet l W J W 7 Mama/1 July 28, 1925.

N. C. RENDLEMAN METALLIC STRUCTURAL ELEMENT,

2 Sheets-Sheet 2 Filed Feb. 15. 1922 War/72 me C fla/mle/zzazz,

Patented July 28, 1925.

UNITED STATES 1,547,607 PATENT OFFICE;

NORMAN C. RENDLEMAN, OF DORMONT, PENNSYLVANIA, ASSIGNOR, BY MESNE AS-SIGNMENTS, TO JONES &: LAUGHLIN STEEL CORPORATION, OF PITTSBURGH, PENN-SYLVANIA, A CORPORATION OF PENNSYLVANIA.

METALLIC STRUCTURAL ELEMENT.

AppIication filed February 13, 1922. Serial No. 536,382.

To all whom it may concern:

Be it known that I, NORMAN 0. Burton:- MAN, a citizen of the UnitedStates, and a resident of Dormont, county of Allegheny, State ofPennsylvania, have invented an Improvement in Metallic StructuralElements, of which the following is a specification.

My invention aims to provide improved metallic beams, columns and otherstructural elements intended to carry or resist heavy loads or stresses,they being commonly rolled shapes such I-beams, T-beams, channels, etc.,

and of the type having latticed, trussed or open webs.

In the accompanying drawings by way of example there is illustrated onepractice of the invention in connection with an I-beam. Figure 1 showsin elevation and in cross-section a slitted I-beam; Figure 2 is alongitudinal section of the same after the reduction and elongation ofthe web by rolling; Figure 3 shows in perspective one manner ofseparating the opposite flanges and thereby forming the truss-membersfrom the web; Figure 4 is r a view in elevation of the finishedillustrative beam; Figures 5 and 6 are enlarged cross-sectional views onthe lines VV and VIVI, respectively of Figure 4[ The entire operation isadvantageously performed upon the beam or other shape as it comes fromthe finishing pass of the roll in -mill, and without reheating. Thisresu ts in great economy, and gives a better product since the metal isnot subjected to possible deterioration by repeated heating. The beam ifrolled in usual manner rows, one row adjacent each of the flanges, or inother cases there may be more than three rows;

From the shear the beam is passed through a rolling-mill, the rolls ofwhich operate only upon the web, leaving the opposite flanges free, andthe effect of this I rolling is uniformly to reduce and elongate the webof the beam without changing the length of the opposite flanges. ThlSoperaweb portion of the beam at the discharge side of the roll pass,thus giving the web portion of the beam the general form shown in Figure2.

The spreading of the opposite flanges may be accomplished as preferred,or as determined by the particular shape of the beam' or other sectionbeing operated upon. In the case of the I-beams it is preferred toaccomplish this spreading by passing the rolled section longitudinallyover gradually diverging side guides 5 as shown in Figure 3.

which bends without injuriously stretching the slit formed member,bringing the article to the finished'width. Then if found hecessary ordesirable it may be subjected to another rolling operation, though thatmay not always be necessary.

The pass between the rolls may of course be a plain pass, which willresult in the truss-members having a general rectangular form incross-section. But to make the truss-members of such cross-sectionalform as to give them maximum'strength, it is preferred to form the rollpass so as to impart to the metal of the web between each row of slits aflanged or ribbed form, such for example as shown inFigure 5 of thedrawings, which is essentially the form of an I-beam,- and when theflanges are pulled apart the truss-members will consequently have thiscross-sectional form. Their form at the points of their junction witheach other is shown in Figure 6.

The extent of elongation ofthe portion of the web subjected to rollingmay be controlled to suit the desired length of the trussmembers, sothat when the side margins of the beam are se arated to expand the beamto its lattieed sbape the longitudinal bows or undulations of theslitted portion of the web produced by the rolling operation will bestraightened out but not stretched a ,preciabl By varying the length ofte to provide the most suitable shape of lattice worak for the purposefor which it is to be use It Will be apparent that the method abovedescribed is not the sole means of producing articles embodying thepresent invention, which may be incorporated in beams and articles of avariety. of shapes having a latticed, trussed or open web between theopposite margins or plates. Flat reticulated plates may be used to greatadvantage in the construction of roadways, and they have other valuableuses as well. For that reason in the appended claims the term latticedelement is used generally to designate inclusively beams, plates orother metallic shapes made in accordance with the invention hereinillustrated.

Heretofore it has been proposed to elongate the slit-formed areas orportions of the plate or web by stretching the same, as by seizing andseparating the marginal portions or beads or by sinking or deflectingsuch portions under lateral pressure or action; but all stretching ofsuch slit-formed portions results in an impairment or injuriousdeformation of the stretched portions. This deformation maybe evidencedin various aspects such as inequalities in cross-sectional areas orconfigurations due to structural differences at various points in theslitformed portions or it may be evidenced by deformations in themetallic structure itself, such for example as an impaired homogeneity.

By rolling or otherwise elongating the;

' slit-formed portions of the web under pressure or by compression, andpreferably preliminary to lateral spreading and bending, a definite andpredetermined cross-section may be assured and a resultant controlledstructural condition of equal or greater density or homogeneity may behad in the bent and spread product, thus greatly adding to the strengthand efficiency of the completed beam or plate. I

I claim as my invention:

1. A rolled metal trussed structural element having continuous flangemembers and web connecting members integral therewith and of uniformphysical properties throughout all parts, each of said connectingmembers having an elongated structure of uniform cross-sectional areafrom end to end.

2. As a new article of manufacture, an integral rolled and bent latticedelement the diagonal members of which are of substantially uniformcross-section and free from stretch deformations.

3. A latticed element havingopposite marginal portions connected byintegral oblique truss-members, said truss-members having a flanged orribbed cross-sectional form.

4. A latticed element having opposite marginal portions connected byintegral intersecting truss-members, thus forming an intermediatelatticed structure, said trussmembers having a flanged or ribbedcrosssectional form.

5. As a new article of manufacture, a rolled metal latticed elementcomprising marginal portions continuous from end to end and connectingmembers integral therewith and having uniform physical properties andhomogeneous structure throughout the element.

6. A latticed element having opposite marginal portions connected byintegral oblique truss-members, said truss-members having a flanged orribbed cross-sectional form of uniform physical properties with theremainder of the element.

In testimony whereof, I have signed my name to this specification thiseleventhday of February A. D. 1922.

NORMAN C. RENDLEMAN.

